Hello.
I purchased an MP573 about 9 months ago. It has worked perfectly this entire time.  Suddenly its giving me garbled/distorted sound.  I've changed slot in the box, changed wires, interface but its definitely the unit.  All other units provide great clear sound.  This went from sounding pristine to unusable.  The problem is that I didn't build it myself and it was a used unit probably for a years.  Is there anything specific that goes bad on these after a while.  Is there someone in the US that I can send it to for repair or maybe just some help?  If not, what component would cause such a problem.  
I really like this preamp.